Electronic equipment such as televisions, telephones, radios and computers are often constructed of solid state devices. Solid state devices operate based on the movement of charge carriers. Accordingly, solid state devices have no moving parts.
Solid state devices are generally preferred in electronic equipment because they are extremely reliable, very small and relatively inexpensive. Solid state devices may be transistors, capacitors, resistors and the like. Such devices are often formed as part of an integrated circuit.
Solid state devices are typically formed by depositing, growing, patterning and etching a series of layers. Different layers may comprise conducting, semiconducting or insulating material. Often, such layers are anisotropically etched to form the various elements of a solid state device. Anisotropic etches may also be used to remove layers without damaging previously formed elements. An anisotropic etch may be a reactive ion etch (RIE) or the like. A problem with anisotropic etches, however, is that they often leave a residual layer of contaminants. These contaminants may interfere with later semiconductor processing such as silicide formation.